Applicator brush with cylindrical ferrule and angled tip

ABSTRACT

A brush for applying a flowable product to a work surface is provided having an elongate handle extending along a central axis and a cylindrical tuft of bristles, the bristles each having a terminal end and a base. A cylindrical ferrule is provided having a first end attached to the handle and a second end from which the tuft protrudes. The ferrule secures the handle to the base of the bristles and the ferrule and tuft cooperate with the central axis. The terminal ends of the bristles form an angled profile and define a generally elliptical plane.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to brushes, and in particular, to an applicator brush having a cylindrical ferrule and angled tip adapted for improved retrieval, application and distribution of product.

2. The Prior Art

Brushes made with natural or synthetic bristles are used for a variety of activities involving the application of product. Specially designed brushes are used where precise control is needed in the amount and location of distribution of product. For example, in applying cosmetics and in creating works of fine art.

A brush having pillared bristles is disclosed in U.S. Published Application 2004/0003478 that is designed for use with a stencil mask as a fabric paintbrush or as an artist's paintbrush.

There are numerous cosmetics provided in an array of forms designed for application to the skin, namely the face. Regardless of the form of a cosmetic, e.g., whether in liquid, semi-liquid or solid forms, a primary concern is achieving a balanced, smooth and proper application of the product in a desired amount to the desired location(s).

With respect to cosmetic products in solid form, powders, in particular, present particular challenges in their application. For example, cosmetic products such as blush (rouge), foundation or eye shadow commonly are provided in powder form. It is highly desirable to apply powdered cosmetics so as to produce a smooth, natural and well-blended appearance. Various types of applicators exist for applying powdered products, including bristle brushes, sponges, sponge-tipped swabs or other types of padded applicators. However, due to the nature of a powdered product, such applicators often deposit the cosmetic as a defined stripe or spot or result in a streaked application, thus producing an un-natural and unattractive appearance.

For example, numerous existing cosmetic brush applicators typically are provided with a rounded or curved bristle head or ‘tuft’ configuration. Namely, brushes are provided with bristles having a hemispherical or curved shape at the top of the tuft or bristles which are arranged in a fan-shaped configuration. Brushes having a tuft whereupon the height of the bristles on one side is higher than the other are also provided; for example, U.S. Pat. Nos. 6,513,183 and 6,039,051 to Dorf are directed to a makeup brush having a curved tuft and a head that is less thick than wide (see e.g., FIG. 7) whereupon the height of bristles on one side of the width is higher than at the opposite side of the width and each side of the width forms a curved portion. However, while some prior art brushes may show a partially angled bristle head, they typically employ a flattened ferrule, thus resulting in a brush with bristles held in a flattened configuration (compare the front and rear views of FIGS. 3A, 3B with the side view of FIG. 4 in Dorf).

U.S. Pat. No. 6,210,060 describes a brush for applying nail varnish consisting of elastomeric material. The brush includes a small number of short bristles that are stapled into the base of the brush handle. U.S. Pat. No. 5,689,872 discloses an artist's tool featuring an impermeable silicone tip that is attached to the base of the handle by a screw or crimped by a ferrule.

Accordingly, an improved applicator brush, in particular, an applicator brush for providing greater precision, ease of use and smoother, natural finish during application of product is highly desirable.

SUMMARY OF THE INVENTION

The present invention provides an improved applicator brush having bristles arranged in a substantially cylindrical formation and secured at a first end via a cylindrical unitary ferrule or bushing, wherein a second end of the bristles forms an angulated profile. Advantageously, a brush according to the present invention provides improved take-up and application of flowable products via a specially shaped and configured tuft which facilitates uniform distribution of a product (e.g., cosmetic substances) both during priming (take-up of product) of the brush and product application. It is to be noted that a brush according to the present invention is not limited to use in cosmetic applications, but may be utilized with advantageous effect in other applications, such as art and crafts, painting, etc., and with a variety of substances, preferably flowable, in solid, liquid or semi-solid form.

In one embodiment, a brush according to the present invention is provided comprising a brush comprising an elongate handle extending along a central axis and a cylindrical tuft of bristles, the bristles each having a proximate base end and a terminal distal end. A cylindrical ferrule is provided having a first end attached to the handle and a second end from which the tuft protrudes. The ferrule encloses and attachment between the handle and the base of the bristles. The terminal ends of the bristles form an angled profile and define a generally elliptical plane. The ferrule may be provided with a rolled-in flange on the side where the bristles exit.

These and other aspects, features and advantages of the present invention will be described or become apparent from the following detailed description of preferred embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exemplary front view of a brush according to an embodiment of the present invention;

FIG. 2 is an exemplary side view of a brush according to an embodiment of the present invention;

FIG. 3 is an exemplary rear view of a brush according to an embodiment of the present invention;

FIG. 4A is a top plan view of the brush of FIG. 3;

FIG. 4B is a partial cross-sectional view taken along the line IVB-IVB from FIG. 4A.

FIG. 5 is a top perspective view of a brush according to an aspect of the present invention;

FIG. 6A is a side view of bristle displacement during simulated use of a brush according to an aspect of the present invention;

FIG. 6B is a schematic view of contact patches created by the brush in use;

FIG. 7A is an exemplary view of a brush positioned for product take-up according to an aspect of the present invention; and

FIGS. 7B and 7C are alternate schematic views of partial contact patches created by the brush in use.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Referring now to FIGS. 1-5, a brush 100 according to the present invention is shown comprising a handle 101 having a ferrule 103 attached at a first end 105, the ferrule or bushing 103 preferably being substantially cylindrical in shape and circular in cross-section and including an inwardly protruding flange 107 at an end remote from its point of attachment with the handle 101. The handle 101 is preferably substantially elongate in form along a central axis 109, and may be tapered and/or ergonomically shaped to aid in balance, grip, and handling. A plurality of bristles 102 is provided to form a tuft 111, which is retained by the ferrule 103. That is, the ferrule 103 is provided for enclosing an attachment of the handle 101 to a base of the tuft 111. The handle 101, ferrule 103 and tuft 111 may share a common central axis 109. The bristles are secured to the handle, within the ferrule in any suitable manner, for example, by being potted in epoxy.

The bristles 102 may comprise synthetic fibers (e.g., extruded thermoplastic materials), natural fibers (e.g., boar's hair, mink, squirrel hair, sable hair, pony hair, etc.) or any combination of both. In one embodiment, the bristles may be treated to impart antimicrobial characteristics; that is, the bristles 102 may comprise, e.g., synthetic bristles treated or impregnated with an antimicrobial agent or compound, such as silver in colloidal form, sulphur, or various chemicals as, e.g., disclosed in U.S. Pat. No. 6,108,847 to Microban Products Company, the disclosure of which is incorporated herein by reference thereto. Exemplary thermoplastics include polypropylene, styrene, polystyrene, polyethylene, ABS, PVC, polycarbonate, polyamide, polyester or polyurethane. Thermoset plastics may also be used.

The tuft 111 is generally cylindrical in shape and in a preferred embodiment includes an angled head (e.g., so as to form a sloped profile. As shown in the side view of FIG. 2, a profile of the terminal ends 113 of the tuft bristles preferably forms a substantially straight but angled line (e.g., a slope) from point “A” to point “B.” That is, in a preferred embodiment, the terminal ends 113 of the bristles 102 lie in a generally elliptical plane 501 that intersects the cylindrical tuft 111 at a non-orthogonal angle 207 with respect to the central axis 109.

FIG. 2 shows an angle 207 of approximately 60 degrees as demonstrative of an exemplary ‘non-orthogonal angle’ of intersection of the elliptical plane 211 with respect to the central axis 109; however, it is noted that the elliptical plane 211 may intersect at any non-perpendicular angle to the central axis 109. In one embodiment, an angle 205 (angle of the elliptical plane 211 with respect to perpendicular axis 209) may comprise a value between greater than 0 degrees to about 80°. For one set of brushes, the angle 205 may comprise about 10°0 to about 50°. In another set of brushes, the angle 205 may comprise, e.g., about 20° to about 40°. The disclosed exemplary angle ranges advantageously preserve the features of the present invention while providing flexibility via varying levels of angulation of the brush head.

The thickness of each individual bristle 102 is preferably in the range of about 0.03 mm to about 0.25 mm. For greater uniformity, bristles having several different diameters ranging from about 0.07 mm to about 0.15 mm may be provided. A number of bristles in tuft 111 of the brush 100 is preferably provided such that a density of the bristles is in the order of at least about 150 bristles per square millimeter. A blend of bristles of different diameters may be incorporated. The disclosed density of the tuft bristles and blend advantageously provides additional control and superior application of an applied product (e.g., cosmetic substances, etc.) as well as enhancing antimicrobial effect when using, e.g., antimicrobial bristles. For an exemplary diameter of 20 mm of ferrule 103 according to the present invention, about 50,000 bristles may be provided, although a number of bristles provided may comprise about 25,000 to about 75,000. It is to be noted that a ferrule according to the present invention may comprise any diameter in accordance with varying brush sizes. Depending on the diameter of the ferrule 103, more or less bristles may be provided to preferably at least meet the above-disclosed minimum bristle density. For example, a larger number of finer bristles, may have a bristle density of 500-600 bristles/mm². In another example, a smaller number of coarser bristles may have a bristle density of 80-100 bristles/mm².

As the bristles are secured in the ferrule 103, the inwardly protruding flange 107 of the ferrule 103 advantageously provides additional compression of/compressive contact with the base of the tuft 111 so as to further facilitate, e.g., achievement and maintenance of a desired bristle density. As shown, e.g. in FIG. 4A, the inner diameter of the flange 107 is represented by 401. As can be seen in FIG. 4B, the rolled in flange 107 compresses the bristles and presents a closed face, compared with a straight tube. That is, the edge has been rolled concentrically inward into alignment with the outermost bristles. The overall inner diameter of the ferrule may be reduce by 10 to 20% in the region of the flange. With tightly packed bristles, there is almost no clearance for product to enter into the ferrule. In addition, the outer curved surface 107 a helps to deflect stray product away from the base of the brush. This construction is in sharp contrast to crimped ferrules. For crimping, a straight section of fairly thin tubular material is needed in order to flatten out the cylinder. Forming a flange greatly strengthens the integrity of a tube, making it difficult to flatten or crimp in any predictable, i.e. uniform, manner. Accordingly, the design of the invention calls for the bristles to be secured by means other than frictional engagement with a crimped ferrule.

Despite the increased bristle density and cylindrical shape of the tuft 111, a brush according to the present invention boasts exceptional uniformity in bristle length. For example, at least 95% of the bristles 102 constituting the tuft 111 according to the present invention have a length which is advantageously within about 1.0 mm of the exemplary defined plane 211. This uniformity in bristle length along e.g., the elliptical plane 211 provides the flat, angled head of the tuft as described above with minimal variation in bristle length.

FIG. 5 depicts the tuft 111 showing a top perspective view of the exemplary elliptical plane 211. Namely, the terminal ends 113 of the bristles 102 define a base plane (e.g., elliptical plane 211), and specifically define, e.g., a substantially circular or elliptical shape 501. The contact patch 501 a created by full planar contact without any bristle displacement, is shown in solid line in FIG. 6B. Line segment 502 a represents the minor axis of the ellipse.

FIG. 6A is a side view of bristle displacement during exemplary simulated use of a brush according to an aspect of the present invention. According to one mode of use, when brush 100 is moved in a direction X along a work surface 601, the bristles along side 203 remain substantially parallel with respect to the central axis 109 while the bristles from approximately a midpoint (central axis 109) to the side 201 are dragged behind, in direction Y. The contact patch 501 b, shown in dotted line, created by full planar contact with bristle displacement, is shown in FIG. 6B. Thus for applying large amounts of product, the brush allows a variable contact patch in the direction of the major axis, while providing significant control over lateral application of product in the direction of the minor axis. Line segment 503 b represents the major axis of the ellipse. The solid line portion being the major axis of the brush in its normal state, and the combined solid and dotted line portions being the major axis of the brush upon bristle displacement.

A tuft 111 of a brush 100 according to the present invention is thus preferably cylindrical, with an angled head having a flat top, the ends 113 of the bristles substantially uniformly defining an elliptical plane 211. Advantageously, the angle of the tuft 111 facilitates holding of the brush at a desired and correct angle to, e.g., the face to apply and blend a product (e.g., a cosmetic) on the face with a smooth, even finish. It is to be noted that the term “product” may comprise any flowable substance, whether in solid, liquid or semi-solid forms and may comprise, e.g., cosmetics, paints, inks, etc. A brush according to the present invention permits greater precision in product application, with the angle of the brush head allowing for a correct and desired amount of product to be picked up accurately without, e.g., undesirable clumping of the product. For example, the longer edge 201 or “toe” of the tuft provides the user with greater control in product application, thus providing the user with the ability to use smaller amount of product while also allowing greater precision and control in smaller areas of application (e.g., in cosmetic applications, around the eyes and nose of the face). The angular, flattened tuft head provides a smoother fit and conformity to a product surface; this in conjunction with the circular shape of the brush head allows for product to be applied evenly, with improved blending of product, a smoother finish and no clumping of product due, e.g., to uneven fibers. Thus, in cosmetic applications for example, the cylindrical shape of the brush head combined with the angled bristles provide the ability to work from the center of the face and blend product more naturally out to the hairline.

FIG. 7A is an exemplary view of a brush positioned for product take-up according to an aspect of the present invention. For even product distribution and take-up of product onto a brush, it is desirable to orient the brush head such that the surface of its tuft is level with the surface of the product. Advantageously, the angulated tuft according to the present invention facilitates this objective. That is, as the brush 100 is held by the user's hand 701, the angled tuft 111 is facilitates positioning of its flattened head such that the end of the tuft 111 is substantially parallel to the surface 703 of the product 705. Thus the brush 100 facilitates and makes it natural for the user to achieve correct positioning during product take-up.

FIG. 7B illustrates product application using a small portion of the tip of the brush. For example, the handle is held straight up or nearly straight, and the tip is gently dabbed against the surface onto which product is to be applied. FIG. 7C illustrates product application using a larger portion of the tip of the brush. For example, the handle is held straight up, and the tip is more firmly dabbed against the surface onto which product is to be applied. In each case where partial bristle contact is made, the contact patch is a semi-circular region. The border on the left hand side of FIGS. 7B and 7C is shown as slightly arcuate, but may also be straight or arcing in the opposite direction, depending on the angle, force, bristle selection, density, etc.

It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of our claims. Although illustrative embodiments of the present invention have been described, it is to be understood that the present invention is not limited to those precise embodiments, and that various other changes and modifications may be affected therein by on skilled in the art without departing from the scope or spirit of the present invention. All such changes and modifications are intended to be included within the scope of the invention as defined by the appended claims. 

1. An applicator brush comprising: an elongate handle extending along a central axis; a cylindrical tuft of bristles, the bristles each having a proximate base end and a distal end, wherein the tuft comprises a blend of bristles of varying diameters in the range of 0.03 mm to 0.25 mm; a cylindrical ferrule having a first end attached to the handle and a second end from which the tuft protrudes, the ferrule for enclosing the attachment of the handle to said proximate base end of the bristles; and wherein substantially all of said distal ends terminate near a flat plane having an elliptical shaped periphery that meets the cylindrical tuft at a non-orthogonal angle.
 2. The brush according to claim 1, wherein the elliptical plane intersects the central axis at a non-orthogonal angle.
 3. The brush according to claim 1, wherein the angle of the elliptical plane with respect to the central axis is in the range of about 20° to about less than 90°.
 4. The brush according to claim 1, wherein the angle of the elliptical plane with respect to a central axis is in the range of about 40° to about 80°.
 5. The brush according to claim 1, wherein the ferrule includes an inwardly rolled flange at the second end for compressing the base of the tuft.
 6. The brush according to claim 5, wherein the flange provides an outer deflection surface for deflecting product away from the proximate base end of the bristles.
 7. The brush according to claim 5, wherein the flange comprises an end surface against which the bristles are compressed to prevent product from traveling toward the proximate base end of the bristles.
 8. The brush according to claim 1, wherein the flange compresses bristles on the order of tens of mm in diameter to a density on the order of 100's of bristles per square millimeter.
 9. The brush according to claim 1, wherein at least 95% of said bristle distal ends terminate within about 1.0 mm of the elliptical plane.
 10. The brush according to claim 1, wherein the bristles comprise antimicrobial synthetic fibers.
 11. The brush according to claim 1, wherein the bristles comprise natural fibers treated with an antimicrobial agent.
 12. The brush according to claim 1, wherein the ellipse includes a major axis and a minor axis, so that upon dragging the brush in the direction of the major axis, the bristles can spread out in the direction of the major axis without substantially spreading out in the direction of the minor axis.
 13. The brush according to claim 1, wherein the tuft comprises bristles of varying diameters in the range of about 0.07 mm to about 0.15 mm.
 14. The brush according to claim 1, wherein the longer bristles comprise a tip end of the brush, and wherein in use of the tip end provides a semi-circular contact patch.
 15. The brush of claim 2, wherein upon pivoting the brush to the non-orthogonal angle, substantially all of the distal ends form a planar contact patch.
 16. The brush of claim 15, wherein the planar contact patch is oval or elliptical.
 17. The brush of claim 16, wherein the major axis of the elliptical contact patch increases with greater bristle displacement.
 18. The brush according to claim 17, wherein the ellipse includes a major axis and a minor axis, so that upon dragging the brush in the direction of the major axis, the bristles can spread out in the direction of the major axis without substantially spreading out in the direction of the minor axis.
 19. The brush according to claim 8, wherein the flange compresses bristles of varying diameters on the order of tens of mm in diameter to a density on the order of 100's of bristles per square millimeter, wherein the non-orthogonal angle of the elliptical plane with respect to the central axis is in the range of about 40° to about 80°, and wherein upon pivoting the brush to the non-orthogonal angle, substantially all of the distal ends form a planar contact patch having an elliptical shape, and wherein substantially all of said bristles are disposed within about 1 mm of the planar contact patch.
 20. The brush according to claim 1, wherein a density of the bristles comprises at least about 150 bristles per square millimeter. 